Cooling device



July 30, 1940. LYMAN 2,209,604

COOLING DEVICE Filed Nov, 12, 1956 3 Sheets-Sheet l K. E. LYMAN COOLING DEVICE July 30, 1940.

Filed Nov. 12, 1936 K. E. LYMAN July so, 1940.

COOLING DEVICE Filed No 12, 1936 s' Sheets-Sheet s Patented-July 3Q, 1940 UNITED STATES- PATENT .oFFicE 2,209,604 I 000mm nnvrcn' Kenneth E. Lyman, Chicago, lli.', assignor to Borg-Warner Corporation, Chicago, III., a corporation of illinois 4 '3 Claims. Thisinvention relates to cooling devices employing solid, gas-emanating refrigerant such as 4 solid carbon dioxide or the like. 7

It is also an object of the invention to provide a cooling unit wherein the cooling medium also functions as insulation.

Another objectof the invention resides in the provision of a cooling unit operated in such a manner as to substantiallyeliminate undesired insulation efiect due to refrigerant.

It is a further object of the invention to provide means within ready reach of the driver or other person occupying the vehicle or other place in which the device in accordance with the invention is installed, for manual regulation and' control of'the rate of cooling.

The invention also contemplates the provision of an automatic control for the device.

Further objects and advantages of the invention will appear as the description proceeds.

The invention, in preferred forms, is illustrated inthe accompanying drawings, in which:

Figure 1 is a vertical sectional view thru a cooling unit embodying the invention;

Figure 2 is a, horizontal sectional view taken substantially as indicated by .the line ,II-II in Figure 3 is a broken vertical section-elevation taken .substantially as indicated by the line' v .lIIlII in Figure 1; and

Figure 4 is a view showing an automobile installation of a cooling unit" in accordance with the invention. I

Referring now particularly to. the drawings, there is illustrated generally a, cooling, unit em-" bodying the invention andadapted to' be portable or of a permanently stationary-character. The unit may comprise-a cabinet I with its side and bottom portions formed of metallic or other 1ining;2 and sheathing 3 between which thermal insulation 4 of any suitable charactersuch as kapok is located.

I A partition 5 forms with a wall portion in detail hereinafter.

application November 1936, Serial No.-110,456-

of the lininga duct or chamber l communicating with the main chamber r compartment 8 through an opening 9 in the pa ition adjacent the bottom of the cabinet. preferably fixedly secured a grid or grille ll) of wire mesh or the like in the compartment 8. This grid is adapted to support one or more blocks H of dry ice such as solid carbon dioxide, ora

quantity of such substance in the form of snow, for example, in a screen-like or other suitable container (not shown), whlchunay be introduced through any suitable door l2 which may form a Above the opening 9 there is' part of the cabinet. Such door will of course be suitably insulated as by having non-metallic contact with the remaining structure when the door is closed. To insure against complete covering of the grid, one or more innerside wall'portions and/omit desired,-the partition 5 may be I formed with one or more open corrugations as shown at it.

Gasproduced by sublimation of the solid refrigerant courses down through the grid It and the opening a and up through the duct 1 which it leaves adjacent the upper part of the cabinet, where it enters a conduit it encased in suitable heat-insulation packing t covered by sheathing ll. At it the conduit affords an intake for a blower is operated by a suitable motor 20, all forming part of the superstructure 2!. The motor may be driven by the power plant or other source of power in the car or other installation,

' a suitable switch (not shown) being also provided. 1

Between the top 22 and bottom 23 of the superstructure there is a partition 25, aiiording thereabove a duct 25; providing a discharge opening for the blower l9. Below the partition there is pro vided another conduit 2t which will be described Sumce it to state at this point that no communication is permitted between the ducts 25 and 26, but communication between the duct 25 and the interior 8 of the cabteriding transversely through and sealed from the conduit or duct 26.

.It is accordingly apparent'that provision is made for the complete cycling or excursion of the refrigerant gas. Any moisture'that maycollect,

inetis established by means of passages 25d ex such as that resulting from entry oi atmospheric air when the dooris opened, my be discharged In accordance with the present invention, pro

' vision is made for a. greatly increased .air cooling eii'ect over what has been the case heretofore.

-through a sump iL suitably located, when the screw cap 21a is removed.

To'this end, the'conduit or compartment 26 has air intake and discharge openings 28 and 29,

respectively at'its terminals. Air from the inlet 28 is acted upon by a blower 30adjacent said inlet. The blower is mounted for rotation preferably by the motor 20 and discharges into the remainder of the conduit at 3|. From the discharge space 3| and up tothe conduit outlet 29,

the conduit 26 constitutes a radiator core as at 32. The passages 25a extending through this core are preferably of oval cross section with the, major axes parallel to the direction of air new in the core, to offer reduced omtruction to the air flow and increased radiation between the air and the refrigerant gas flowing thru said passages.

It will thus be seen that a forced draft and continuous flow of the refrigerant gas is afiorded by the gas blower l9, and a like effect on the air to be cooled is obtained by use of the air blower 30, and the large area of contact of the I moving gas with the side walls and interior structure of the core 32 insures the transfer of adequate heat from the air to the gas flowing through the passages 25a. In order to augment the heat transfer'the wall 33 of the core 32 may' .be formed with relatively open corrugations so that the walls of each corrugation will be spaced apart sufiiciently to obviate crowding andthus will not interfere with the proper flow of the portion of the gas directly contacting the same.

In addition, it is pointed out that refrigerant gas has a relatively high insulating property. If the gas is allowed to move at a slow rate as, for example, when it moves by convection, the friction of the confining wall with the gas forms a substantially stationary skin or layer of gas which, serves as an insulating medium and substantially reduces the passage of heat from the air to the gas. By running the gas at substantially increased velocity such as thatobtained by a'forced draft from the blower la, the skin friction is overcome and the gas does not perform any insulating function'and accordingly there is a substantially greater passage of heat from the air to the gas. This is a matter of considerable importance when it is realized that carbon dioxide gas, for example, at or near thetemperature of sublimation has about six times the insulating value of cork.

It is to be appreciated that carbon dioxide as is evolved from solid carbon dioxide, in an atmosphere of such gas, at about 109 F., and

accordingly is capable of having a very great cooling eifect even though it may pass through the cooling cycle as many asptwenty times, more or less, without reinforcement by cooler gas or contactwith the solid refrigerant before a con dition of thermal equilibrium between the gas and the air occurs.

While the insulating material 4 may be of any character desired, it is preferably of cork, loose felt, wool, kapok or such other material as will allow the gas to infiltrate and permeate the same and retain the gas. Accordingly, adjacent the top of the cabinet the lining 3 is pierced at 34 and the lining of the superstructure is pierced at 35 to allow the refrigerant gas to pass from the interior 8 of the cabinet and thepassage 2! into the packing 4. 'When'the packing is permeated with the gas, it has an insulating value which would be aflorded by a wall oi. kapok or cork several times the thicknessof the packing alone. This will be evident from the fact that the gas has great insulating properties when at rest, and it is in a condition of substantial rest when it permeates the insulating material.

A control valve at any suitable location as at the entrance of the conduit l4 as shown at 31 or in the conduit l4 as shown at 36, may be provided to regulate the rate of cooling afforded by the unit. Such a valve may be automatically con-v trolled as by thermostatic means 38 influenced by the temperature of the gas from the chamber wide range of body sizes and may be installed in a small space such as at one side of a luggage compartment as shown at 40, closed by a door 4011, where it is unobtrusive and will not materially encroach upon the space remaining available for luggage purposes. I

The intake and discharge ends of the air conduit 26 may be located as conditions may require or suggest. For example, in an automobile installation, it may be advantageous to position the intake at the deck 42 at one end of the rear seat 43, as shown in Fig. 4 at 44, the discharge end 45 leading to a tube 46 attached to or built into the ceiling and extending forwardly to the middle or any other part of the body or may branch oifas at 41 to discharge at the desired points. .The discharge could be provided in a floor duct which could open at the floor board, or in any other suitable part of the car.

The flow of gas is indicated by full line arrows as at 48 and the as at 49.

' The system,'as stated, may be regulated to provide the desired degree of cooling. In'vestiga tions have shown that a diflerential of substantially 6 between the exterior and the interior of the confined space equipped with the cooling unit is'preferred for the human system, since sucha differential provides the desired amount of desired.

The unit need not necessarily have the shape illustrated since it may be made substantially flat or'in any other desired shape to be accommodated under the floor oi the luggage compartment or in any other inobtrusive place.

The material forming the lining andcasing of the cabinet and othersheet material parts need flowof air by dash line arrows not necessarily be made of metal but if desired may be oi non-metallic material such as composition and may be molded into, the desired shapes. It will be observed that the unit may be arranged conveniently with the'cabinet door l2 readily accessible for replenishment of the cabinet as shown in Fig. 4.

I am aware that many changes may be made and numerous-details of construction may be varied through a wide range without departing from the principles of this invention, and 1-.therefore do notpurpoee limiting the patent granted hereon otherwise than necessitated by the prior art.

I claim as my invention: 1.- A cooling unit having an insulated fluid cir,

' cuit adapted to .contain gas-emanating refrigerant' and two compartments separated by an upstanding wall open at its lower end to establish communication between the compartments, means providing forced draft for the gas in said circuit, an air radiator at the upper part of said wall and sealed from and dividing said circuit,

'and tubular means sealed from and passing through said radiator and establishing communication between the divided portions of said circuit.' a

2. In an air cooling system for ,utilizing solid Co: as the refrigerant; an insulated chamber having means to support a quantity oi'said refrigerant, an air conducting heat exchanger traversing said chamber, connections to said heat exchanger from the exterior of the chamber, for conducting air from a space to be conditioned, through said heat exchanger and back to said space, a blower for forcibly circulating iii the air through said connections and heat exchanger, a blower for forcibly circulating gaseous CO sublimated from said refrigerant body, in contact with said radiator so as to overcome the tendency of said gaseous CO: to form an insulating layer in contact with the radiator and a motor common to both of said blowers, having a shaft on which said blowers are mounted.

3. An air cooling unit for a motor vehicle, having a closed refrigerant gas circuit divided by an open air circulating radiator, the interior of which is sealed from said refrigerant circuit, said circuit having a passage traversing said radiator perpendicularly to the path of air flow therethrough to establish communication between the divided parts of the circuit and having a com- -xmmmnnnmu. as 

